Kumeyaay Lake Campground in San Carlos is San Diego's only urban campground, operating 46 primitive campsites along the shoreline of a former sand-and-gravel quarry lake inside Mission Trails Regional Park in the 92119 ZIP. Reservations are available on a first-come, first-served basis for Friday and Saturday nights at a flat nightly rate, and eighteen sites are designated tent-only while sites 20, 22, 24 through 45, and 47 accept RVs, campervans, and trailers with no electrical, water, or sewer hookups provided. Each campsite includes a fire ring for charcoal or prepacked San Diego County firewood and a picnic table, and two comfort stations provide flush toilets and hot showers. Dogs are permitted in the camping area on a six-foot leash but are restricted from park trails and the north shore, which is fenced to protect nesting habitat for the federally endangered least Bell's vireo, and campers use Rancho San Carlos Pet Clinic on Lake Murray Boulevard for pre-trip vet checks and trail-related injuries. The lake holds bluegill, largemouth bass, and catfish, and anglers with a valid California fishing license can cast from the southern shoreline during sunrise-to-sunset hours. Monday through Thursday, the campground converts to day-use access for hikers and cyclists who stage from the parking area to reach Cowles Mountain, Kwaay Paay Peak, and the Five Peak Challenge loop that traverses the park's ridgeline. An amphitheater and a replica Kumeyaay 'ewaa — a traditional willow-branch hut — sit near the lake's western inlet where a cement bridge channels water from the San Diego River into the reservoir. The San Diego Natural History Museum maintains interpretive signage along a self-guided nature walk on the south shore, documenting the riparian habitat that has regenerated since the H.G. Fenton Material Company's Monarch Plant ceased gravel operations in the early 1970s. Evening campers returning from the trails gravitate toward San Carlos's dining strip on Lake Murray Boulevard, where McGuffie's Live pairs a pub menu with a live-music calendar that runs into the late hours on weekends. The campground entrance sits off Father Junipero Serra Trail at the Bushy Hill Drive intersection, accessible from Mission Gorge Road via the CA-52 exit at Mast Boulevard.